This research project involves studies of the chemical and physiochemical properties of hormones with lactogenic, growth-promoting and other properties and correlations of chemical features with biologic and immunologic activity. The project includes amino acid sequence determination and detailed characterization of hormone derivatives produced by chemical and enzymic methods. The project also involves physiologic and pathophysiologic chemical and enzymic methods. The project also involves physiologic and pathophysiologic studies of the synthesis, storage and secretion in vitro and in vivo of pituitary and placental hormones and a model system of parathyroid hormone production. Extensive use is made of the technique of radioimmunoassay to study hormone release in vitro in short term incubation, organ and tissue culture systems.